The present invention relates to an apparatus and a method for performing a cardiac by-pass procedure, also referred to herein as an anastamosis. This invention further relates to grafts for use in the repair, replacement, or supplement of a medical patient's natural body organ structures or tissues. The present invention also relates to methods and apparatus for delivering a graft to an operative site in a patient and for installing the graft at that site.
Several procedures are known for revascularizing the human heart in order to treat a patient with one or more occluded coronary arteries. One of the earliest of these procedures involves exposing the heart by a midline sternotomy. Following surgical exposure of the heart, the patient's aorta and vena cava are connected to a heart/lung machine to sustain vital functions during the procedure. The beating of the heart is stopped to facilitate performance of the procedure. Typically, a suitable blood vessel, such as a length of the patient's saphenous (leg) vein, is harvested for use as a graft. The graft is used to create a new, uninterrupted channel between a blood source, such as the aorta, and the occluded coronary artery or arteries downstream from the arterial occlusion or occlusions. A variation of the above procedure involves relocating a mammary artery of the patient to a coronary artery. Although the above-described sternotomy procedures grow more successful each year, the invasiveness of these procedures, the stopping of the heart, and the necessity for general anesthesia are significant disadvantages. Indeed, these disadvantages preclude the use of sternotomy procedures on many patients.
More recently, less invasive procedures have been developed for revascularizing the heart without using the heart/lung machine (“beating heart” procedures). Two problems with “beating heart” coronary artery repair are the active movement of the beating heart and the challenge of creating anastamoses to the aorta and coronary arteries while they are filled with blood. Various devices and methods have been devised to attempt to immobilize the heart and create a bloodless field to facilitate such beating heart procedures. Drugs may be administered to the patient to slow the heart during the procedure, stabilizing devices may be placed on the surface of the heart, and shunts or snares may be introduced into or around the coronary arteries to allow stabilization of the coronary arteries and construction of the coronary anastamoses in a bloodless field.
A less invasive method for revascularizing the human heart involves gaining access to the thoracic cavity by making incisions between the patient's ribs. This procedure is known as a thoracotomy. A thoracotomy procedure is substantially less traumatic than a midline sternotomy, but it is still too traumatic for some patients. An even less invasive procedure is known as thoracostomy, which involves the surgical creation of ports in the patient's chest to obtain access to the thoracic cavity. Specially designed instruments can be inserted through the ports to allow the surgeon to revascularize the heart without causing more significant trauma from a midline sternotomy. Thoracostomy bypass procedures are less traumatic than sternotomy bypass procedures, but the introduction of stabilization devices through thorocostomy ports is cumbersome, impractical, and of limited utility. Furthermore, bypasses to the coronary arteries that are located on dependent portions of the heart are not readily possible with this technique.
Several patents have recently been filed or issued in the field of graft and stent assemblies and methods for use thereof. Of particular interest are the following U.S. Pat. Nos. 5,702,412; 5,944,019; 5,976,178; 6,026,814; 6,063,114; 6,068,637; 6,074,416; 6,120,432; 6,186,942; 6,196,230; 6,206,912; 6,253,769; 5,456,712; 5,522,882; and U.S. patent application Ser. No. 2001-0003985 A1. All patents, applications, and publications mentioned here and throughout the application are incorporated in their entirety by reference herein and form a part of the present application.
Accordingly, there is a need for a new improved method and apparatus for performing an anastamosis.